To be eligible for NDA, you must have passed 10+2 or equivalent from a recognized board. There are three segments in NDA- Army wing, Naval Wing and Air Force. For Naval and Air Force and Cadet Entry Scheme in INA, the minimum criterion is that, the candidate must has passed 10+2 with Physics and Mathematics from a recognized board. For Army Wing, there is no such barrier. Now coming to the NDA Exam pattern, there are two papers which you have to appear for- Mathematics and General Ability Test (GAT). 120 questions will be there from Mathematics and 150 questions from GAT. GAT consists of topics like English (Grammar, Vocabulary etc), Physics, Chemistry, General Science, History, Freedom Movement, Geography and Current events. Mathematics syllabus follows topics such as Algebra, Matrices, Determinants, Vector Algebra, Integral Calculus, Differential Equations, Statistics and Probability, Trigonometry, Differential Calculus, Analytical Geometry.
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